Safety closure

ABSTRACT

A safety closure for a container is disclosed. The container has a threaded neck, a shoulder, and one or more lug recesses and preceding camming surfaces on the periphery of the shoulder. The cap has an internally threaded inner wall and an outer, flexible, spaced concentric skirt. The skirt has one or more downwardly protruding lugs on its lower edge. Rotation of the cap relative to the bottle causes the lug to engage a camming surface. Continued rotation of the cap leads the lug into the lug recess, releasably locking the cap upon the container neck. The cap is removed by first applying an inward squeezing force to the cap skirt thereby flexing the lug outwardly to disengage the lug from the lug recess after which the cap can be rotated freely in a direction to unscrew the cap. In another embodiment, the container neck and cap have one or more partial threads so that the cap is thrust onto the neck which also cams the lug or lugs outwardly and then the cap is turned through only a partial revolution to engage the threads and move the lug into the recess.

United States Patent Gach et al. Nov. 6, 1973 SAFETY CLOSURE [75] Inventors: Peter P. Gach, Evansville, Ind.; ABSTRACT Henry K. Leonard, Toledo, Ohio [73] Assignee: Sunbeam Plastics Corporation,

Evansville, Ind.

A safety closure for a container is disclosed. The container has a threaded neck, a shoulder, and one or more lug recesses and preceding camming surfaces on the periphery of the shoulder. The cap has an internally threaded inner wall and an outer, flexible, spaced concentric skirt. The skirt has one or more downwardly protruding lugs on its lower edge. Rotation of the cap relative to the bottle causes the lug toengage a camming surface. Continued rotation of the cap leads the lug into the lug recess, releasably locking the cap upon the container neck. The cap is removed by first applying an inward squeezing force to the cap skirt thereby flexing the lug outwardly to disengage the lug from the lug recess after which the cap can be rotated freely in a direction to unscrew the cap. In another embodiment, the container neck and cap have one or more partial threads so that the cap is thrust onto the neck which also cams the lug or lugs outwardly and then the cap is turned through only a partial revolution to engage the threads and move the lug into the recess.

10 Claims, 22 Drawing Figures [22] Filed: Aug. 4, 1972 [2]] Appl. No.: 278,101

Related U.S. Application Data [63] Continuation-impart of Ser. No. 232,161, March 6,

1972, abandoned.

[52] U.S. Cl. 215/9 [51] Int. Cl B65d 55/02 [58] Field of Search 215/9, 43; 222/182 [56] References Cited UNITED STATES PATENTS 3,698,584 lO/l972 Miller 215/9 3,633,789 l/l972 Markowitz 215/9 Primary ExaminerGeorge T. Hall Att0rneyAllen Owen et al.

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sum nor 4 SAFETY CLOSURE This application is a continuation-in-part of our application Ser. No. 232,161 filed Mar. 6, 1972, now abandoned.

BACKGROUND OF THE INVENTION Many substances stored in the home, such as detergents, cleaning compounds, insecticides and pharmaceuticals, are potentially harmful to children. Such substances are commonly stored in various containers. Ideally, any such container should be easily openable by the intentional act of an adult, but significantly difficult for a young child to open.

Many safety closures have been proposed in the past. However, most of these efforts have produced closures which have various defects. Some proposed closures have relatively complex structures, requiring a multiplicity of parts, such as separate inner and outer cap elements, ring sleeves, or a special key opener. These structures have been expensive to produce because of their complexity, and have not been widely adopted.

Unitary safety caps have also been proposed. Many such caps have a disadvantage in that the cap must be sufficiently flexible to permit the cap to be squeezed and flexed outwardly. As a result, the effectiveness of the seal is reduced, creating a serious leakage problem.

SUMMARY OF THE INVENTION According to the invention, a unitary cap is provided for closing the opening of a container having a neck and a shoulder at the base of and surrounding the neck. The cap is fabricated from a resilient material and has a circular top, an inner depending, annular wall, and an outer, concentric skirt. The container neck and the inner cap wall have cooperating means for retaining the cap on the container which are engaged, at least in part, by rotation of the cap onto the neck. The inner cap wall is designed to be stiffer than the outer skirt so that the outer skirt is relatively more flexible than the inner cap wall which seals the container neck. The outer skirt has one or more downwardly protruding lugs. The container shoulder has one or more lug recesses formed on its outer periphery. The container shoulder may have a camming surface preceding the lug recess. In another embodiment, the lug has a camming surface on its inner side. In either embodiment, the last increments of movement of the cap onto the container neck causes the lug to be cammed radially outwardly and final rotation of the cap on the container neck moves the lug circumferentially into alignment with the lug recess. The resiliency of the cap skirt snaps the lug inwardly into the recess to lock the cap against reverse rotation. Removal of the cap is effected by first squeezing the cap to deform the outer skirt to disengage the lug from the lug recess and then rotating the cap off the container.

The object of this invention is to provide an improved safety closure apparatus which may be easily opened by an adult, but which will limit the access of children to the contents of the container.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view in elevation with parts broken away and parts in section of a cap embodying the invention;

FIG. 2 is a plan view of the cap shown in FIG. 1 with parts broken away, being illustrated in its normal configuration;

FIG. 3 is a horizontal cross-sectional view taken along line 3-3 of FIG. 1 and showing the cap in its deformed configuration;

FIG. 4 is a bottom perspective view of the cap shown in FIGS. l-3;

FIG. 5 is a fragmentary view in elevation showing the cap of FIGS. 1-4 illustrating how the cap is flexed to initially disengage the lug from locked position;

FIG. 6 is a fragmentary top perspective view of the container;

FIG. 7 is a fragmentary view partly in vertical section and partly in perspective of a cap for a second embodiment of a container closure in accordance with the present invention;

FIG. 8 is a plan view of a bottle neck and shoulder of the embodiment shown in FIG. 7;

FIG. 9 is a fragmentary, vertical cross section taken along line 99 of FIG. 8 showing the camming lug on an enlarged scale,

FIG. 10 is a view similar to FIG. 8 but of a modification of the embodiment illustrated in FIGS. 7-9;

FIG. 11 is a bottom perspective view of yet another embodiment of a cap for a container closure in accordance with the present invention;

FIG. 12 is a fragmentary top perspective view of a container neck for use with the cap illstrated in FIG. 11;

FIG. 13 is a fragmentary view in elevation of the embodiment of FIGS. 1 1-12 showing the locking lug in an unlocked position;

FIG. 14 is a fragmentary view in elevation of another embodiment of the invention comprising only partial threads on the container neck and cap;

FIG. 15 is a plan view of the safety closure illustrated in FIG. 14;

FIG. 16 is a fragmentary view in front perspective of the neck of a container showing the partial threads of this embodiment illustrated in FIG. 14;

FIG. 17 is a view similar to FIG. 7 but showing the embodiment of the invention illustrated in FIGS.

FIG. 18 is a fragmentary side view in elevation, with parts broken away, showing yet another modification of the invention;

FIG. 19 is a fragmentary horizontal sectional view taken along the line l919 of FIG. 18;

FIG. 20 is a fragmentary view in perspective of the neck portion of the container of the embodiment shown in FIG. 18;

FIG. 21 is a fragmentary view in perspective of the neck and shoulder portion of a container embodying a modification of the invention; and

FIG. 22 is a fragmentary plan view of the container neck shown in FIG. 21.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A container 10 and a cap 11, embodying the invention, are shown in FIG. 1. The container 10 has a bottom 12, side wall 13, a threadedneck 14, and a shoulder 15 extending outwardly from the base of the threaded neck 14 toward the side wall 13. The container shoulder 15 has a pair of opposed camming surfaces 16 and spaced lug recesses 17 at its outer periphery. (As shown in FIG. I, the container has a planar shoulder.) The term shoulder is used herein to designate the portion of the container extending outwardly from the threaded neck 14 toward the side wall 13, regardless of the shape of the shoulder.

The cap 11 has a top 18, and a threaded inner wall 19 which engages the threads on the neck portion 14 of the container 10. An outer, concentric skirt 20 extends from the top 18 downwardly beyond the inner wall 19. In the embodiment shown in FIGS. 16, the skirt 20 has a pair of opposed locking lugs 21. Preferably, a vertical reinforcing rib 22 is provided on the skirt 20 above each lug 21.

The cap is made of a suitable stiffly resilient plastic material. The inner wall 19, as reinforced by its threads, has a thickness such that it is relatively rigid and non-flexible compared to the skirt 20 so as to provide the necessary sealing engagement, together with the torque and distortion resistance desired. The outer concentric skirt 20 functions partly as the safety closure assembly locking member. The skirt 20 has such a thickness that it will flex outwardly as the lugs 21 engage and move along the camming surfaces 16 and will restore inwardly when the lugs 21 reach the recesses 17.

To assemble the cap 11 on container 10, the cap 11 is applied to the upper end of the container and rotated in a clockwise direction. As the cap 1 l is rotated, the threaded inner wall 19 engages the threaded container neck 14. Continued rotation causes the lugs 21 to engage the camming surfaces 16. Further rotation of the cap 11 forces the lugs 21 along the camming surfaces 16 until the lugs 21 ride the upper portion of the container side wall 13. Continued rotation snaps the lugs 21 into the respective lug recesses 17.

An effort to remove the cap 11 from the container 10 by rotating the cap 1 l in a counter clockwise direction is prevented by the locking action between lugs 21 and the lug recesses 17. To remove the cap 11, the outer concentric skirt 20 is squeezed inwardly as indicated by the arrows in FIGS. 3 and 5. Squeezing the cap 11 in this manner distorts the flexible skirt 20 and flexes the lugs 21 outwardly (see FIG. 3). Counterclockwise rotation of the cap 11 then removes the cap 11. Because the inner wall 19 is relatively rigid and non-flexible, when the outer skirt 20 is distorted the threaded inner wall 19 is not deformed. If the threaded inner wall 19 were easily distorted, the sealing power would be reduced, and the container 10 would be unsatisfactory for normal use, especially for liquid products.

FIGS. 7 through 10 illustrate a modified embodiment of the invention. Lugs 21a formed on an outer concentric skirt 200 are slightly beveled. The safety closure is assembled as previously described by rotating a cap Ila in a clockwise direction. As the lugs 21a engage a camming surface 16a, on a shoulder a of a container 100, the beveled edge on the lugs 210 causes the lugs 21a to be flared outwardly before they engage in the lug recesses 17a. As seen in FIG. 9, the inner beveled surface of the lug 21a acts as a cam surface. This rnodification allows the use of a container 10a having a smaller camming surface 16a (see FIG. 8). Indeed, in this embodiment no discrete camming surface is required because, as shown in FIG. 10, the beveled cam surface on the lugs 21a may engage an unbeveled edge on the shoulder 15a to urge the lugs 21a outwardly as they approach the recesses 17a.

FIGS. 11 and 13 illustrate another embodiment of the invention. In this embodiment the container 10b and cap 11b are similar to the container 10 and cap 11 illustrated in FIGS. 1 through 6. Instead of opposed lugs 21 and opposed lug recesses 17, a single lug 21b, camming surface 16b and lug recess 17b are provided for the lockable safety closure.

The embodiment of the invention illustrated in FIGS. 14-17, inclusive, differs from the earlier disclosed embodiments of the invention in that the means for retaining a cap 110 on a container 10c are partial threads generally indicated by the reference number 23 on a neck 14c of the container and by the reference number 24 on the inner surface of a cap side wall 13c. The cap also has an outer skirt 20c and one or more downwardly-extending lugs 21c. A corresponding number of lug recesses 17c are formed at the corner of a container shoulder 15c and camming surfaces 16c are provided.

The partial threads 23 and 24 preferably extend slightly less than 90 circumferentially of their respective members so that the circumferential spacing between the ends of the partial threads 23 and 24 is greater than 90. The lugs 210 are centrally located circumferentially relative to the partial threads 24 on the cap wall 130, and the camming surfaces are centrally located relative to the blank spaces lying circumferentially between the ends of the partial threads 23 on the container neck 14c. The camming surfaces 16c are centered relative to the spaces between the ends of the partial threads on the container neck 14c.

To place the cap 110 on the container 10c, the user aligns the partial threads 23 of the cap 110 above the circumferential area between the ends of the partial threads 23 on the container 100. This can easily be done by centering the lugs 21c above the camming surfaces 16c. The user then thrusts the cap 11c axially onto the neck 14c, pushing downwardly until the tabs 21c engage the camming surfaces 160 and are flexed outwardly. The user then rotates the cap 110 (clockwise in FIG. 16) to engage the two partial threads 23 and 24, and continues to rotate the cap 11c relative to the container 106 until the lugs 21c align with their respective recesses 17c whereupon the flexibility of the outer cap skirt 20c snaps the lugs 21c into the recesses 17c.

To remove the cap of this embodiment of the invention, the user presses inwardly on opposite sides of the lower portion of the skirt 20c intermediate the two lugs 216, thus deforming the skirt 20c inwardly and springing the lugs 210 out of their recesses 170. The user may then turn the cap 11c approximately 90 (counterclockwise in FIG. 16) to disengage the partial threads 23 and 24. He then simply pulls the cap 1 1c off the container 10c.

Referring now to FIGS. 18-20, inclusive, a container 10d and a cap 11d are shown. The container 10d has a reduced-diameter side wall portion 13d and a threaded neck 14d. A shoulder 15d is molded to provide two semi-circular camming surfaces 16d, each of which terminates in a lug recess 17d. The lug recesses 17d are diametrically opposed to each other.

The cap 11d has a fiat top 18d, an inner wall 19d which is internally threaded to mate with external threads on the threaded neck 14d, and an outer skirt 20d.

The cap 11d, like the earlier-described caps embodying the invention, has a pair of downwardly-extending lugs 21d at the lower edge of the skirt 20d. When the cap 11d is rotated onto the container neck 14d, the lugs 21d engage the respective camming surfaces 16d and are flexed outwardly by reason of the flexibility of the skirt 20d compared to the stiffer inner wall 19d. As the cap 1 1d is rotated to final closed position, the lugs 21d reach alignment with the lug recesses 17d and the resiliency of the outer cap skirt 20d snaps them inwardly into the recesses 17d.

In common with the earlier-described embodiments of the invention, the cap 11d may be removed only after inward radial pressure is exerted at two sides of the cap 11d spaced 90 from the respective lugs 21d, thus to deform the outer skirt 20d to move the lugs 21d radially outwardly beyond the shouldered recesses 17d, whereupon the cap may be rotated in a direction to remove the cap (counterclockwise in FIG. 19).

The only distinction between the embodiment of the invention illustrated in FIGS. 18-20, inclusive, and earlier embodiments of the invention lies in the fact that the container d shown in FIGS. 18-20 has a reduced wall portion 13d and the shoulder d extends between the neck 14d and the reduced diameter portion 13d of the container side wall.

The embodiment of the invention illustrated in FIGS. 21 and 22 includes the features discussed with respect to the earlier modifications and comprises an additional feature.

A container, fragmentarily indicated by the reference number 10e has a sidewall portion Be, a threaded neck 14c, and a shoulder 153 at their junction. In common with the earlier embodiments of the invention, two opposed camming surfaces 16e extend part way around the edge of the shoulder 15e. A series of lug recesses 172 are located at the end of each of the camming surfaces 16e for the reception and retention of cap lugs 2le of a cap not shown in FIGS. 21 and 22, but which is substantially identical to the previously disclosed caps 11 11d.

By the provision of several recesses in each of the series l7e after a cap is screwed onto the container 10e and its lugs 2le engage the camming surfaces l6e to be flared outwardly, the user continues to rotate the cap with the lugs 2le snapping sequentially into and out of the recesses in the series 17e until the cap has been tightened onto the container 102 to the degree desired.

The presence of a series of recesses l7e' for engagement by each of the cap lugs 2le provides for secure tightening and safety retention of the cap on the container 10:: even if its liner gradually is squeezed thinner by repeated replacements of the cap. In addition, the provision of the series of lug recesses l7e compensates for the fact that the heights of container necks l4e and the depths of the caps to be used thereon, may not be maintained within tolerances. For example, if the threads on the cap were to be spaced slightly lower relative to its inner top surface, a locking lug 2le might snap into its respective recess before the cap had tightly squeezed the liner to seal the bottle against the escape of liquid or of a volatile material. This is particularly important when automatic assembly of the caps on the bottles is taking place. With the series of recesses l7e the chuck of the automatic capping machine can be set with a predetermined torque so that the capping machine will rotate the caps onto the bottles with that torque until the lugs 2le finally engage in one of the several recesses in the series l7e when the cap is properly seated.

It may also be desirable in an embodiment according to FIG. 21 and 22 to slightly taper the lugs 212 as shown in FIG. 22, so that they seat more firmly in the generally sawtooth recesses in the series 17e.

Safety closures embodying the invention have particular advantages over many so-called safety closures or child proof caps and containers which result from their specific design. The container can be formed by a simple blow molding process. The cap is a single piece so that there is no need for the assembly of separate parts. Because the cap can be screwed onto the bottleneck without requiring any special manipulations, containers and caps embodying the invention can be assembled automatically after the containers are filled, i.e., automatic capping equipment can be utilized to place the caps on the containers on an assembly line basis.

Various other advantages and modifications of the above described preferred embodiments will be appar' cut to those skilled in the art and may be made without departing from the spirit and scope of the appended claims.

What we claim is:

l. A safety closure comprising a container and a cap, said container having a bottom, a sidewall, a neck and an annular shoulder extending between said neck and said sidewall, and at least one lug recess in said container adjacent the periphery of said shoulder, said cap having a top, an inner wall depending from said top, cooperating means on said closure neck and said inner wall for retaining said cap in closed position on said container, an outer skirt depending from said top in concentric relationship to said inner wall, said skirt including at least one depending lug having a lower portion extending below the bottom of said inner wall, and camming means for guiding said lug toward such lug recess.

2. A safety closure according to claim 1 wherein said camming means comprises a bevelled inner surface on the lower end of said depending lug, whereby said bevelled surface engages said shoulder as said cap is moved downwardly.

3. A safety closure according to claim 1, wherein said camming means comprises a container camming surface on said shoulder adjacent its periphery, whereby when the cap is moved downwardly, said lug engages said camming surface and is urged outwardly.

4. A safety closure according to claim 3, wherein said cap includes two opposed lugs depending from said skirt and said container shoulder has two opposed camming surfaces 5. A safety closure according to claim 1, wherein said cooperating means consists of external threads on said neck and internal threads on said inner wall.

6. A combination safety closure comprising a container and a unitary screw-on cap, said container having a bottom, a cylindrical sidewall, a threaded neck and shoulder extending between said threaded neck and said sidewall, said container shoulder having at least one camming surface defined at its outer periphery, at least one lug recess at the outer periphery of said container shoulder, said screw-on cap having a top, a downwardly extending threaded inner wall for mating with said threaded neck of said container, and an outer,

spaced, concentric, resilient skirt depending from said top, said skirt extending below said inner wall, said skirt having at least one downwardly protruding locking lug, said lug overlying and being in an engageable relationship with said container camming surface, whereby when said cap is screwed onto said container, said lug engages said camming surface and is moved outwardly and whereby continued rotation of said cap moves said lug to said recess and the resiliency of said skirt snaps said lug into said lug recess, releasably locking said cap upon said container neck.

7. The safety closure of claim 6 wherein said camming surface of said container shoulder consists of a bevelled edge extending toward each lug recess.

8. The safety closure of claim 6 wherein said protrudtainer neck. 

1. A safety closure comprising a container and a cap, said container having a bottom, a sidewall, a neck and an annular shoulder extending between said neck and said sidewall, and at least one lug recess in said container adjacent the periphery of said shoulder, said cap having a top, an inner wall depending from said top, cooperating means on said closure neck and said inner wall for retaining said cap in closed position on said container, an outer skirt depending from said top in concentric relationship to said inner wall, said skirt including at least one depending lug having a lower portion extending below the bottom of said inner wall, and camming means for guiding said lug toward such lug recess.
 2. A safety closure according to claim 1 wherein said camming means comprises a bevelled inner surface on the lower end of said depending lug, whereby said bevelled surface engages said shoulder as said cap is moved downwardly.
 3. A safety closure according to claim 1, wherein said camming means comprises a container camming surface on said shoulder adjacent its periphery, whereby when the cap is moved downwardly, said lug engages said camming surface and is urged outwardly.
 4. A safety closure according to claim 3, wherein said cap includes two opposed lugs depending from said skirt and said container shoulder has two opposed camming surfaces
 5. A safety closure according to claim 1, wherein said cooperating means consists of external threads on said neck and internal threads on said inner wall.
 6. A combination safety closure comprising a container and a unitary screw-on cap, said container having a bottom, a cylindrical sidewall, a threaded neck and shoulder extending between said threaded neck and said sidewall, said container shoulder having at least one camming surface defined at its outer periphery, at least one lug recess at the outer periphery of said container shoulder, said screw-on cap having a top, a downwardly extending threaded inner wall for mating with said threaded neck of said container, and an outer, spaced, concentric, resilient skirt depending from said top, said skirt extending below said inner wall, said skirt having at least one downwardly protruding locking lug, said lug overlying and being in an engageable relationship with said container camming surface, whereby when said cap is screwed onto said container, said lug engages said camming surface and is moved outwardly and whereby continued rotation of said cap moves said lug to said recess and the resiliency of said skirt snaps said lug into said lug recess, releasably locking said cap upon said container neck.
 7. The safety closure of claim 6 wherein said camming surface of said container shoulder consists of a bevelled edge extending toward each lug recess.
 8. The safety closure of claim 6 wherein said protruding lug has a bevelled inner surface.
 9. The safety closure of claim 6 wherein said container shoulder and sidewalls define a pair of circumferentially spaced lug recesses, and wherein said concentric skirt has a pair of circumferentially spaced lugs complementary with said recesses, for releasably locking said cap to said container.
 10. In a combination safety closure according to claim 6, the improvement comprising a circumferentially extending series of lug recesses in the container shoulder which are sequentially engaged by the locking lug when the cap is screwed more tightly onto the container neck. 